1. Field of the Invention
This invention relates to high speed rotary sheet forming apparatus for making pads for the interiors of box containers and the like.
2. Description of the Prior Art
As heretofore known, pads are used in boxes to separate layers of bottled or canned goods. For example, a multi-cell partition in some packaging operations is opened and placed on the bottom of a box, and the cells are filled with bottles of a product being shipped. A pad is then placed over the partition to cover the contents in the cells. The packing is then completed by placing another partition on the pad, filling its cells with the bottled product, and sealing the box for shipment. In other packing operations, where such a box is filled with jars of fruits or the like, further protection is provided by the use of additional pads placed on the bottome of the box initially, and on the top of the upper tier of partitions.
It is desirable that the length and width of such pads shall be close enough to the interior dimensions of the box so the pad edges slidably glide into place when they are inserted. Sharp corners for such pads are a hindrance to desired high volume packing of goods, and also to quick unpacking. At a grocery, for example, an employee is often frustrated at attempts to remove a pad so as to get access to filled partitions covered by the pad. Accordingly, it is common practice to form pads with rounded corners. Finger space is thus available at the corners to facilitate proper placement in packing, and removal of pads when unpacking.
Heretofore, the best known method of forming pads with rounded corners involves the use of reciprocally operated punch apparatus. Typically, a punch is vertically movable periodically to punch cusp-shaped slugs out of the edge of a roll of chipboard. The slug passes with the punch into a mating die part, the slug falling through such mating part. The male punch is lifted to clear the material, which passes to a cutter which cuts it along a line that bisects cusps at the opposite edges.
This type of machinery suffers a number of drawbacks. Reciprocal action inherently subjects parts to undesired stresses, with consequent undesired down time for replacement and repair of worn items. Also, production is inherently limited. For example, it is known that for cutting only, a rotary cutting setup is significantly faster than a reciprocal cutting approach. However, while rotary apparatus is known for cutting pads, there is no known satisfactory rotary apparatus for both cutting such sheets and providing rounded corners for them.